As it happens, the _median_ household income is about the same as the _mean_ GDP per capita in the US right now. That's because incomes typically have distributions in which the mean is a lot higher than the median, as your link notes. Note that GDP per capita is also higher than mean per-capita income for people because there are non-household components of GDP (e.g. you would need to count unrealized capital gains as income to get closer to "income" approximating GDP).
I agree that household income is a more interesting thing to compare to for this case, though, but even more interesting would be comparing to similar households. Otherwise you're comparing the income of our hypothetical family of 4 to the incomes of 1-person households, incomes of households containing just a student, incomes of households containing one or two retirees, and so forth.
I agree that household income is a more interesting thing to compare to for this case, though, but even more interesting would be comparing to similar households. Otherwise you're comparing the income of our hypothetical family of 4 to the incomes of 1-person households, incomes of households containing just a student, incomes of households containing one or two retirees, and so forth.
Luckily for us, such information is out there; http://www.census.gov/hhes/www/income/data/statistics/4perso... lists the median family-of-four income in the US at $67,000 or so in 2005 (though by state the median ranges from about $50k to about $90k, which shows the problem with talking about aggregate "United States" numbers). http://www.census.gov/hhes/www/income/data/Fam_Inc_SizeofFam... has similar numbers for a few years later... http://www.census.gov/hhes/www/income/data/historical/househ... has quite a bit higher numbers than that for 2011 ($75k median nationally), which is a bit surprising to me, actually.
None of which answers the question of how reasonable an income of $30k is for a family of 4, of course.